2018 Tile Calculator & Estimator | Tile Flooring & Ceiling Square ...27 Sep 2017 ... Whether you are tiling the floors, the shower or the walls, you should start by getting exact measurements of the area. When you know the area's total square footage, multiply that number by 115 percent. This accounts for mistakes, the edges of the room or even slight miscalculations in your measurements. Once you know exactly how much tile you need, you can start crafting a budget. Try to get your figure down to a specific price per square foot, which will make it&nbsp;...